Answer:
Angular acceleration will be 
Explanation:
We have given that mass m = 0.18 kg
Radius r = 0.32 m
Initial angular velocity 
And final angular velocity 
Time is given as t = 8 sec
From equation of motion
We know that 


So angular acceleration will be 
Steps 1 and 2)
The variables are W = work, P = power, and t = time. In this case, W = 9514 joules and P = 347 watts.
The goal is to solve for the unknown time t.
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Step 3)
Since we want to solve for the time, and we have known W and P values, we use the equation t = W/P
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Step 4)
t = W/P
t = 9514/347
t = 27.4178674351586
t = 27.4 seconds
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Step 5)
The lawn mower ran for about 27.4 seconds. I rounded to three sig figs because this was the lower amount of sig figs when comparing 9514 and 347.
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Note: we don't use the mass at all
Answer:
The heat transferred through the wall that day is 13728 BTUs
Explanation:
Here, we have the area of the wall given as
Area of wall = 2 × Length × Height + 2 × Width × Height
Length = 15 feet
Width = 11 Feet and
Height = 9 feet
Therefore, the area = 2×15×9 + 2×11×9 = 468 ft²
Temperature difference is given by
Average outside temperature - Wall temperature = 40 - 18 = 22 °F
Therefore the heat transferred through the wall that day (24 hours) at 18 sq.ft. hr/BTU is given by;
468 × 22 × 24/18 = 13728 = 13728 BTUs.
Answer:
I think is B but I'm not sure
Acceleration is defined as rate of change in velocity
So we can write its formula as

here we know that
= final velocity = 56 m/s
= initial velocity = 7.6 m/s
t = time interval to change the velocity = 3 s
now we will plug in all values in the above equation



so here roller coaster will accelerate at rate of 16 m/s^2 and hence correct answer is "option d"